android_kernel_samsung_msm8976/arch/x86_64/kernel/early-quirks.c
Andi Kleen b026872601 [PATCH] x86-64: Try multiple timer variants in check_timer
Instead of adding all kinds of more quirks try various timer
routing variants in check_timer.

In particular this tries to handle quirks from:
- Nvidia NF2-4 reference BIOS: wrong timer override
- Asus: Wrong timer override but no HPET table
- ATI: require timer disabled in 8259
- Some boards: require timer enabled in 8259

We just try many of the the known variants in the hopefully right order
in check_timer.

Trying pin 0/2 on Nvidia suggested by Tim Hockin.

TBD Experimental. Needs a lot of testing

Signed-off-by: Andi Kleen <ak@suse.de>
2006-12-07 02:14:06 +01:00

126 lines
2.9 KiB
C

/* Various workarounds for chipset bugs.
This code runs very early and can't use the regular PCI subsystem
The entries are keyed to PCI bridges which usually identify chipsets
uniquely.
This is only for whole classes of chipsets with specific problems which
need early invasive action (e.g. before the timers are initialized).
Most PCI device specific workarounds can be done later and should be
in standard PCI quirks
Mainboard specific bugs should be handled by DMI entries.
CPU specific bugs in setup.c */
#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/pci_ids.h>
#include <asm/pci-direct.h>
#include <asm/proto.h>
#include <asm/dma.h>
static void via_bugs(void)
{
#ifdef CONFIG_IOMMU
if ((end_pfn > MAX_DMA32_PFN || force_iommu) &&
!iommu_aperture_allowed) {
printk(KERN_INFO
"Looks like a VIA chipset. Disabling IOMMU. Override with iommu=allowed\n");
iommu_aperture_disabled = 1;
}
#endif
}
#ifdef CONFIG_ACPI
static int nvidia_hpet_detected __initdata;
static int __init nvidia_hpet_check(unsigned long phys, unsigned long size)
{
nvidia_hpet_detected = 1;
return 0;
}
#endif
static void nvidia_bugs(void)
{
#ifdef CONFIG_ACPI
/*
* All timer overrides on Nvidia are
* wrong unless HPET is enabled.
* Unfortunately that's not true on many Asus boards.
* We don't know yet how to detect this automatically, but
* at least allow a command line override.
*/
if (acpi_use_timer_override)
return;
nvidia_hpet_detected = 0;
acpi_table_parse(ACPI_HPET, nvidia_hpet_check);
if (nvidia_hpet_detected == 0) {
acpi_skip_timer_override = 1;
printk(KERN_INFO "Nvidia board "
"detected. Ignoring ACPI "
"timer override.\n");
printk(KERN_INFO "If you got timer trouble "
"try acpi_use_timer_override\n");
}
#endif
/* RED-PEN skip them on mptables too? */
}
static void ati_bugs(void)
{
}
struct chipset {
u16 vendor;
void (*f)(void);
};
static struct chipset early_qrk[] = {
{ PCI_VENDOR_ID_NVIDIA, nvidia_bugs },
{ PCI_VENDOR_ID_VIA, via_bugs },
{ PCI_VENDOR_ID_ATI, ati_bugs },
{}
};
void __init early_quirks(void)
{
int num, slot, func;
if (!early_pci_allowed())
return;
/* Poor man's PCI discovery */
for (num = 0; num < 32; num++) {
for (slot = 0; slot < 32; slot++) {
for (func = 0; func < 8; func++) {
u32 class;
u32 vendor;
u8 type;
int i;
class = read_pci_config(num,slot,func,
PCI_CLASS_REVISION);
if (class == 0xffffffff)
break;
if ((class >> 16) != PCI_CLASS_BRIDGE_PCI)
continue;
vendor = read_pci_config(num, slot, func,
PCI_VENDOR_ID);
vendor &= 0xffff;
for (i = 0; early_qrk[i].f; i++)
if (early_qrk[i].vendor == vendor) {
early_qrk[i].f();
return;
}
type = read_pci_config_byte(num, slot, func,
PCI_HEADER_TYPE);
if (!(type & 0x80))
break;
}
}
}
}